Vadim V. Tarasov

Biogenic synthesis of Zinc oxide nanostructures from Nigella sativa seed: Prospective role as food packaging material inhibiting broad-spectrum quorum sensing and biofilm

Bacterial spoilage of food products is regulated by density dependent communication system called quorum sensing (QS). QS control biofilm formation in numerous food pathogens and Biofilms formed on food surfaces act as carriers of bacterial contamination leading to spoilage of food and health hazards. Agents inhibiting or interfering with bacterial QS and biofilm are gaining importance as a novel class of next-generation food preservatives/packaging material. In the present study, Zinc nanostructures were synthesised using Nigella sativa seed extract (NS-ZnNPs). Synthesized nanostructures were characterized hexagonal wurtzite structure of size ~24 nm by UV-visible, XRD, FTIR and TEM. NS-ZnNPs demonstrated broad-spectrum QS inhibition in C. violaceum and P. aeruginosa biosensor strains. Synthesized nanostructures inhibited QS regulated functions of C. violaceum CVO26 (violacein) and elastase, protease, pyocyanin and alginate production in PAO1 significantly. NS-ZnNPs at sub-inhibitory concentrations inhibited the biofilm formation of four-food pathogens viz. C. violaceum 12472, PAO1, L. monocytogenes, E. coli. Moreover, NS-ZnNPs was found effective in inhibiting pre-formed mature biofilms of the four pathogens. Therefore, the broad-spectrum inhibition of QS and biofilm by biogenic Zinc oxide nanoparticles and it is envisaged that these nontoxic bioactive nanostructures can be used as food packaging material and/or as food preservative.

Blockade of Neuroglobin Reduces Protection of Conditioned Medium from Human Mesenchymal Stem Cells in Human Astrocyte Model (T98G) Under a Scratch Assay

Previous studies have indicated that paracrine factors (conditioned medium) increase wound closure and reduce reactive oxygen species in a traumatic brain injury in vitro model. Although the beneficial effects of conditioned medium from human adipose tissue-derived mesenchymal stem cells (hMSCA-CM) have been previously suggested for various neurological diseases, their actions on astrocytic cells are not well understood. In this study, we have explored the effect of hMSCA-CM on human astrocyte model (T98G cells) subjected to scratch assay. Our results indicated that hMSCA-CM improved cell viability, reduced nuclear fragmentation, attenuated the production of reactive oxygen species, and preserved mitochondrial membrane potential and ultrastructural parameters. In addition, hMSCA-CM upregulated neuroglobin in T98G cells and the genetic silencing of this protein prevented the protective action of hMSCA-CM on damaged cells, suggesting that neuroglobin is mediating, at least in part, the protective effect of hMSCA-CM. Overall, this evidence suggests that the use of hMSCA-CM is a promising therapeutic strategy for the protection of astrocytic cells in central nervous system (CNS) pathologies.

Approaches for the Development of Drugs for Treatment of Obesity and Metabolic Syndrome

Obesity and metabolic syndrome (MS) are risk factors for diabetes, cancer, some cardiovascular and musculoskeletal diseases. Pharmacotherapy should be used when the body mass index (BMI) exceeds 30 kg/m² or 27 kg/m² with comorbidity. Efficacy and safety of pharmacotherapy depend on the mechanism of action of drugs. In this context, drugs affecting the central and peripheral mediator systems such as cannabinoid receptor antagonists (Rimonabant), neuronal reuptake inhibitor of NE and 5 HT (Sibutramine), neuronal reuptake inhibitor of NE 5-HT DA (Tesofensine), agonist of 5 HT 2C receptors (Lorcaserin) have a high risk of side effects on the central nervous and cardiovascular systems when used for a long period. Apparently, the drugs design targeting obesity should screen safer drugs that affect fat absorption (Orlistat), activate energy metabolism (Adipokines), inhibit MetAP2 (Beloranib) and other peripheral metabolic processes. The use of synergies of anti-obesity drugs with different mechanisms of action is an effective approach for developing new combined pharmaceutical compositions (Contrave®, EmpaticTM, Qsymia et al). The purpose of this article is to review the currently available anti-obesity drugs and some new promising trends in development of anti-obesity therapy.

Medicinal Plants as Protective Strategies Against Parkinson’s Disease

Parkinsons disease is a neurodegenerative disease caused by the loss of dopaminergic neurons in the substantia nigra pars compacta region. An important mechanism contributing to its development is oxidative stress, induced by the imbalance between the endogenous antioxidant defenses and free radicals production. Naturally occurring bioactive compounds exhibit high antioxidant capacity that may help reducing oxidative stress and even reverse the damage induced by ROS. Fruits are particularly rich in phytochemicals with antioxidant effect, and their properties against the development of neurodegenerative diseases are of great interest. This review discusses how the fruits bioactive compounds and synthetic analogs have been assessed for their ability to regulate molecular pathways involved in neuronal survival such as MAPK, Nrf2, and NF-κB, thus elucidating the possible therapeutic and neuroprotective actions of these compounds.

Gliomas: New Perspectives in Diagnosis, Treatment and Prognosis

Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortality is expected to rise in coming years, especially in developing countries. Diagnosis and classification of gliomas have largely relied on tumor histopathologic features that provide limited information regarding response to therapy or prognosis. Current treatment of gliomas is surgery combined with chemotherapy and/or radiotherapy. However, many tumors show a high resistance to these interventions, and recurrences are frequent since conventional therapies do not take into account the unique molecular features of different subtypes of glioma. Molecular genetics provide new insights in classifying gliomas and predicting response to therapy that can range from conventional treatments to new revolutionary therapeutic approaches. This article offers a review of the intracellular signaling pathways involved in carcinogenesis of gliomas, as well as a description of new tools for their diagnosis, prognosis, and treatment with a target-oriented approach.

Is VEGF a Key Target of Cotinine and Other Potential Therapies Against Alzheimer Disease

BACKGROUND The vascular endothelial growth factor (VEGF) is a neuroprotective cytokine that promotes neurogenesis and angiogenesis in the brain. In animal models, it has been shown that environmental enrichment and exercise, two non-pharmacological interventions that are beneficial decreasing the progression of Alzheimer disease (AD) and depressive-like behavior, enhance hippocampal VEGF expression and neurogenesis. Furthermore, the stimulation of VEGF expression promotes neurotransmission and synaptic plasticity processes such as neurogenesis. It is thought that these VEGF actions in the brain, may underly its beneficial therapeutic effects against psychiatric and other neurological conditions. CONCLUSION In this review, evidence linking VEGF deficit with the development of AD as well as the potential role of VEGF signaling as a therapeutic target for cotinine and other interventions in neurodegenerative conditions are discussed.

Nanotechnology for Alzheimer Disease

BACKGROUND Alzheimer disease (AD) typically affects behavior, memory and thinking. The change in brain have been reported to begin approx. 10-20 years before the appearance of actual symptoms and diagnosis of AD. An early stage diagnosis and treatment of this lethal disease is the prime challenge, which is mainly halted by the lack of validated biomarkers. METHOD Recent nanotechnological advancements have the potential to offer large scale effective diagnostic and therapeutic options. Targeted drug (e.g. Rivastigmine) delivery with the help of nanoparticles (NPs) in the range of 1-100 nm diameters can effectively cross the blood brain barrier with minimized side effects. Moreover, biocompatible nanomaterials with increased magnetic and optical properties can act as excellent alternative agents for an early diagnosis. With the high volume of research coming in support of the effective usage of NP based drug delivery in critical environment of CNS, it is quite likely that this approach can end up providing remarkable breakthroughs in early stage diagnosis and therapy of AD. CONCLUSION In the current review, we have presented a comprehensive outlook on the current challenges in diagnosis and therapy of AD, with an emphasis on the effective options provided by biocompatible NPs as imaging contrast agents and drug carriers.

Cotinine: A Therapy for Memory Extinction in Post-traumatic Stress Disorder

Post-traumatic stress disorder (PTSD) is a mental disorder that may develop after exposure to exceptionally threatening or unescapable horrifying events. Actual therapies fail to alleviate the emotional suffering and cognitive impairment associated with this disorder, mostly because they are ineffective in treating the failure to extinguish trauma memories in a great percentage of those affected. In this review, current behavioral, cellular, and molecular evidence supporting the use of cotinine for treating PTSD are reviewed. The role of the positive modulation by cotinine of the nicotinic acetylcholine receptors (nAChRs) and their downstream effectors, the protection of astroglia, and the inhibition of microglia in the PTSD brain are also discussed.

Implications of farnesyltransferase and its inhibitors as a promising strategy for cancer therapy

Ras proteins have been reported to play key role in oncologic diseases. Ras proteins are associated with cellular membranes for its carcinogenic activities through post-translational modifications, including farnesylation. Farnesyltransferase is responsible for a type of Ras membrane targeting, which leads to cancer origin and progression. Inhibitors of farnesyltransferase have been developed as novel anticancer agents. In this review, the role of farnesyltransferase in cancer progression and development has been discussed. Further, the current status of development of farnesyltransferase inhibitors for cancer prevention and treatment has also been reviewed.

Insulin Resistance in Alzheimer Disease: p53 and MicroRNAs as Important Players

Glucose homeostasis is crucial for neuronal survival, synaptic plasticity, and is indispensable for learning and memory. Reduced sensitivity of cells to insulin and impaired insulin signaling in brain neurons participate in the pathogenesis of Alzheimer disease (AD). The tumor suppressor protein p53 coordinates with multiple cellular pathways in response to DNA damage and cellular stresses. However, prolonged stress conditions unveil deleterious effects of p53-evoked insulin resistance in neurons; enhancement of transcription of pro-oxidant factors, accumulation of toxic metabolites (e.g. ceramide and products of advanced glycation) and ROS-modified cellular components, together with the activation of proapoptotic genes, could finally induce a suicide death program of autophagy/apoptosis in neurons. Recent studies reveal the impact of p53 on expression and processing of several microRNAs (miRs) under DNA damage-inducing conditions. Additionally, the role of miRs in promotion of insulin resistance and type 2 diabetes mellitus has been well documented. Detailed recognition of the role of p53/miRs crosstalk in driving insulin resistance in AD brains could improve the disease diagnostics and aid future therapy.